JP4776829B2 - Self-luminous device - Google Patents

Description

【０１３７】
(M.A.Baldo, D.F.O’Brien, Y.You, A.Shoustikov, S.Sibley, M.E.Thompson, S.R.Forrest, Nature 395(1998)p.151.)
上記の論文により報告されたＥＬ材料(Ｐｔ錯体)の分子式を以下に示す。
【０１３８】
【化２】

【０１３９】
(M.A.Baldo, S.Lamansky, P.E.Burrrows, M.E.Thompson, S.R.Forrest, Appl.Phys.Lett.,75(1999)p.4.)
(T.Tsutsui, M.-J.Yang, M.Yahiro, K.Nakamura, T.Watanabe, T.tsuji, Y.Fukuda, T.Wakimoto, S.Mayaguchi, Jpn.Appl.Phys., 38(12B)(1999)L1502.)
上記の論文により報告されたＥＬ材料(Ｉｒ錯体)の分子式を以下に示す。
【０１４０】
【化３】

【０１４１】
以上のように三重項励起子からの燐光発光を利用できれば原理的には一重項励起子からの蛍光発光を用いる場合より３〜４倍の高い外部発光量子効率の実現が可能となる。なお、本実施例の構成は、実施例１〜実施例９のいずれの構成とも自由に組みあせて実施することが可能である。
【０１４２】
[実施例７]
本発明の自発光装置を応用したＥＬディスプレイは、自発光型であるため液晶ディスプレイに比べて明るい場所での視認性に優れ、しかも視野角が広い。従って、様々な電子機器の表示部として用いることが出来る。
【０１４３】
なお、ＥＬディスプレイには、パソコン用表示装置、ＴＶ放送受信用表示装置、広告表示用表示装置等の全ての情報表示用表示装置が含まれる。また、その他にも様々な電子機器の表示部に本発明の自発光装置を用いることが出来る。
【０１４４】
その様な本発明の電子機器としては、ビデオカメラ、デジタルカメラ、ゴーグル型表示装置(ヘッドマウントディスプレイ)、ナビゲーションシステム、音響再生装置(カーオーディオ、オーディオコンポ等)、ノート型パーソナルコンピュータ、ゲーム機器、携帯情報端末(モバイルコンピュータ、携帯電話、携帯型ゲーム機または電子書籍等)、記録媒体を備えた画像再生装置(具体的にはデジタルビデオディスク(ＤＶＤ)等の記録媒体を再生し、その画像を表示しうるディスプレイを備えた装置)などが挙げられる。特に、斜め方向から見ることの多い携帯情報端末は視野角の広さが重要視されるため、ＥＬディスプレイを用いることが望ましい。それら電子機器の具体例を図１１および図１２に示す。
【０１４５】
図１１(Ａ)はＥＬディスプレイであり、筐体３３０１、支持台３３０２、表示部３３０３等を含む。本発明の自発光装置は表示部３３０３にて用いることが出来る。ＥＬディスプレイは自発光型であるためバックライトが必要なく、液晶ディスプレイよりも薄い表示部とすることが出来る。
【０１４６】
図１１(Ｂ)はビデオカメラであり、本体３３１１、表示部３３１２、音声入力部３３１３、操作スイッチ３３１４、バッテリー３３１５、受像部３３１６等を含む。本発明の自発光装置は表示部３３１２にて用いることが出来る。
【０１４７】
図１１(Ｃ)はヘッドマウントＥＬディスプレイの一部(右片側)であり、本体３３２１、信号ケーブル３３２２、頭部固定バンド３３２３、表示部３３２４、光学系３３２５、表示装置３３２６等を含む。本発明の自発光装置は表示装置３３２６にて用いることが出来る。
【０１４８】
図１１(Ｄ)は記録媒体を備えた画像再生装置(具体的にはＤＶＤ再生装置)であり、本体３３３１、記録媒体(ＤＶＤ等)３３３２、操作スイッチ３３３３、表示部(ａ)３３３４、表示部(ｂ)３３３５等を含む。表示部(ａ)３３３４は主として画像情報を表示し、表示部(ｂ)３３３５は主として文字情報を表示するが、本発明の自発光装置はこれら表示部(ａ)３３３４、表示部(ｂ)３３３５にて用いることが出来る。なお、記録媒体を備えた画像再生装置には家庭用ゲーム機器なども含まれる。
【０１４９】
図１１(Ｅ)はゴーグル型表示装置(ヘッドマウントディスプレイ)であり、本体３３４１、表示部３３４２、アーム部３３４３を含む。本発明の自発光装置は表示部３３４２にて用いることが出来る。
【０１５０】
図１１(Ｆ)はパーソナルコンピュータであり、本体３３５１、筐体３３５２、表示部３３５３、キーボード３３５４等を含む。本発明の自発光装置は表示部３３５３にて用いることが出来る。
【０１５１】
なお、将来的にＥＬ材料の発光輝度が高くなれば、出力した画像情報を含む光をレンズ等で拡大投影してフロント型あるいはリア型のプロジェクターに用いることも可能となる。
【０１５２】
また、上記電子機器はインターネットやＣＡＴＶ(ケーブルテレビ)などの電子通信回線を通じて配信された情報を表示することが多くなり、特に動画情報を表示する機会が増してきている。ＥＬ材料の応答速度は非常に高いため、ＥＬディスプレイは動画表示に好ましい。
【０１５３】
また、ＥＬディスプレイは発光している部分が電力を消費するため、省消費電力化のためには発光部分が極力少なくなるように情報を表示することが望ましい。従って、携帯情報端末、特に携帯電話や音響再生装置のような文字情報を主とする表示部にＥＬディスプレイを用いる場合には、非発光部分を背景として文字情報を発光部分で形成するように駆動することが望ましい。
【０１５４】
図１２(Ａ)は携帯電話であり、本体３４０１、音声出力部３４０２、音声入力部３４０３、表示部３４０４、操作スイッチ３４０５、アンテナ３４０６を含む。本発明の自発光装置は表示部３４０４にて用いることが出来る。なお、表示部３４０４は黒色の背景に白色の文字を表示することで携帯電話の消費電力を抑えることが出来る。
【０１５５】
図１２(Ｂ)は音響再生装置、具体的にはカーオーディオであり、本体３４１１、表示部３４１２、操作スイッチ３４１３、３４１４を含む。本発明の自発光装置は表示部３４１２にて用いることが出来る。また、本実施例では車載用オーディオを示すが、携帯型や家庭用の音響再生装置に用いても良い。なお、表示部３４１４は黒色の背景に白色の文字を表示することで消費電力を抑えられる。これは携帯型の音響再生装置において特に有効である。
【０１５６】
図１２(Ｃ)はデジタルカメラであり、本体３５０１、表示部(Ａ)３５０２、接眼部３５０３、操作スイッチ３５０４、表示部(Ｂ)３５０５、バッテリー３５０６を含む。本発明の電気光学装置は、表示部(Ａ)３５０２、表示部(Ｂ)３５０５にて用いることが出来る。
【０１５７】
以上の様に、本発明の適用範囲は極めて広く、あらゆる分野の電子機器に用いることが可能である。また、本実施例の電子機器は実施例１〜実施例５に示したいずれの構成を適用しても良い。
【発明の効果】
本発明の自発光装置によって、点灯時間の差によるＥＬ素子の劣化を回路側で補正し、輝度ムラのない均一な画面の表示が可能な自発光装置を提供することが出来る。
【図面の簡単な説明】
【図１】 本発明の劣化補正機能を有する自発光装置のブロック図。
【図２】 加算処理による補正方法を示した図。
【図３】 減算処理による補正方法を示した図。
【図４】 表示装置と信号補正装置とを同一基板上に一体形成した場合の自発光装置の一例を示したブロック図。
【図５】 アクティブマトリクス型自発光装置の作成工程例を示した図。
【図６】 アクティブマトリクス型自発光装置の作成工程例を示した図。
【図７】 アクティブマトリクス型自発光装置の作成工程例を示した図。
【図８】 アクティブマトリクス型自発光装置の作成工程例を示した図。
【図９】 時間階調方式について説明した図。
【図１０】 発光素子の劣化による画面の輝度ムラの発生を示した図。
【図１１】 本発明の劣化補正機能を有する自発光装置の電子機器への応用例を示した図。
【図１２】 本発明の劣化補正機能を有する自発光装置の電子機器への応用例を示した図。
【図１３】 本発明の劣化補正機能を有する自発光装置のブロック図。
【図１４】 本発明の劣化補正機能を有する自発光装置における、デジタル映像信号入力方式およびアナログ信号入力方式のソース信号線駆動回路のブロック図。
【図１５】 従来の自発光装置の一例を示した図。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a self light emitting device, and more particularly to an active matrix self light emitting device. In particular, the present invention relates to an active matrix self-luminous device using a self-luminous element such as an organic electroluminescence (EL) element in a pixel portion.
[0002]
[Prior art]
In recent years, the spread of self-luminous devices in which a semiconductor thin film is formed on an insulator such as a glass substrate, in particular, active matrix self-luminous devices using TFTs, has become remarkable. An active matrix self-luminous device using TFTs has hundreds of thousands to millions of TFTs in pixel portions arranged in a matrix, and displays an image by controlling the charge of each pixel. ing.
[0003]
Furthermore, as a recent technology, in addition to the pixel TFT that constitutes the pixel, a technology related to a polysilicon TFT that simultaneously forms a drive circuit using a TFT around the pixel portion has been developed. Along with this, self-luminous devices have become an indispensable device for display units of mobile devices and the like, whose application fields have been remarkably expanding in recent years.
[0004]
In addition, as a flat display that replaces an LCD (liquid crystal display), a self-luminous device using a self-luminous material such as an organic EL is attracting attention, and active research is being conducted.
[0005]
FIG. 15A shows an outline of a normal self-light-emitting device. In this specification, description will be made using an organic EL (hereinafter simply referred to as EL) as an example of a self-luminous element. A pixel portion 1504 is arranged in the center of an insulating substrate (eg, glass) 1501. In the pixel portion 1504, a current supply line 1505 for supplying current to the EL element is arranged in addition to the source signal line and the gate signal line. A source signal line driver circuit 1502 for controlling a source signal line is disposed above the pixel portion 1504, and a gate signal line driver circuit 1503 for controlling a gate signal line is disposed on the left and right sides of the pixel portion 1504. Has been. In FIG. 15A, the gate signal line driver circuit 1503 is arranged on both the left and right sides of the pixel portion; however, it may be arranged only on one side. However, the arrangement on both sides is desirable from the viewpoint of driving efficiency and reliability. Input of signals to the source signal line driver circuit 1502 and the gate signal line driver circuit 1503 is performed from the outside through a flexible printed circuit (FPC) 1506.
[0006]
FIG. 15B is an enlarged view of a portion surrounded by a dotted frame 1500 in FIG. In the pixel portion, each pixel is arranged in a matrix as shown in FIG. In FIG. 15B, a portion surrounded by a dotted line frame 1510 is one pixel, and a source signal line 1511, a gate signal line 1512, a current supply line 1513, a switching TFT 1514, an EL driving TFT 1515, a storage capacitor 1516, An EL element 1517 and the like are included.
[0007]
Next, the operation of the active matrix self-luminous device will be described with reference to FIG. First, when the gate signal line 1512 is selected, a voltage is applied to the gate electrode of the switching TFT 1514, and the switching TFT 1514 becomes conductive. Then, the signal (voltage) of the source signal line 1511 is accumulated in the storage capacitor 1516. The voltage of the storage capacitor 1516 is the gate-source voltage V of the EL driving TFT 1515. _GS Therefore, a current corresponding to the voltage of the storage capacitor 1516 flows through the EL driving TFT 1515 and the EL element 1517. As a result, the EL element 1517 emits light.
[0008]
The luminance of the EL element 1517, that is, the amount of current flowing through the EL element 1517, depends on the voltage V of the EL driving TFT 1515. _GS Can be controlled by. V _GS Is a voltage of the storage capacitor 1516, which is a signal (voltage) input to the source signal line 1511. That is, the luminance of the EL element 1517 is controlled by controlling a signal (voltage) input to the source signal line 1511. Finally, the gate signal line 1512 is deselected, the gate of the switching TFT 1514 is closed, and the switching TFT 1514 is turned off. At that time, the charge accumulated in the storage capacitor 1516 is held. Therefore, the V of the EL driving TFT 1515 _GS Is held as is and V _GS A current corresponding to the current continues to flow to the EL element 1517 via the EL driving TFT 1515.
[0009]
Regarding the driving of EL elements, SID99 Digest: P372: “Current Status and future of Light-Emitting Polymer Display Driven by Poly-Si TFT”, ASIA DISPLAY98: P217: “High Resolution Light Emitting Polymer Display Driven by Low Temperature Polysilicon Thin Film Transistor with Integrated Driver ”, Euro Display99 Late News: P27:“ 3.8 Green OLED with Low Temperature Poly-Si TFT ”.
[0010]
Next, a gradation display method of the EL element 1517 will be described. The gate-source voltage V of the EL driving TFT 1515 as described above. _GS Therefore, the analog gradation method for controlling the luminance of the EL element 1517 has a drawback that it is vulnerable to variations in current characteristics of the EL driving TFT 1515. That is, if the current characteristics of the EL driving TFT 1515 are different, the current value flowing through the EL driving TFT 1515 and the EL element 1517 changes even when the same gate voltage is applied. As a result, the luminance, that is, the gradation of the EL element 1517 changes.
[0011]
Therefore, a method called a digital gradation method has been devised in order to reduce the influence of the characteristic variation of the EL driving TFT 1515 and obtain a uniform screen. In this method, the absolute value of the gate-source voltage of the EL driving TFT 1515 | V _GS In this method, gradation is controlled in two states: a state where | is equal to or lower than the lighting start voltage (almost no current flows) and a state larger than the luminance saturation voltage (current close to the maximum flows). In this case, the EL driving TFT 1515 | V _GS If | is sufficiently larger than the luminance saturation voltage, even if the current characteristics of the EL driving TFT 1515 vary, the current value is I _MAX Close to. Therefore, the influence of variations of the EL driving TFT 1515 can be very small. As described above, this method is called a digital gradation method because gradation is controlled in two states, ON state (bright because the maximum current flows) and OFF state (dark because no current flows). ing.
[0012]
However, in the case of the digital gradation method, only two gradations can be displayed as it is. Therefore, a plurality of techniques for increasing the number of gradations in combination with another method have been proposed.
[0013]
One method for achieving multiple gradations is a time gradation method. The time gradation method is a method in which the time during which the EL element 817 is lit is controlled, and gradation is produced according to the length of the lighting time. That is, one frame period is divided into a plurality of subframe periods, and the number of subframe periods that are lit and the length thereof are controlled to express gradation.
[0014]
Please refer to FIG. FIG. 9 simply shows a timing chart of the time gray scale method. In this example, the frame frequency is set to 60 [Hz] and a 3-bit gradation is obtained by a time gradation method.
[0015]
As shown in FIG. 9A, one frame period is divided into subframe periods corresponding to the number of gradation bits. Since there are 3 bits here, 3 subframe periods SF ₁ ~ SF _Three It is divided into. One subframe period further includes an address period (Ta _# ) And sustain (lighting) period (Ts) _# ). SF ₁ Sustain period at Ts ₁ I will call it. SF ₂ , SF _Three Similarly, in the case of Ts ₂ , Ts _Three I will call it. Address period Ta ₁ ~ Ta _Three Are periods in which video signals for one frame are written to the pixels, and the lengths are equal in any subframe period. The sustain period here is Ts ₁ : Ts ₂ : Ts _Three = 2 ² : 2 ¹ : 2 ⁰ = 4: 2: 1 and has a power-of-two ratio. However, even if the ratio of the lengths of the sustain periods is not a power of 2 as described above, gradation can be expressed.
[0016]
As a method of gradation display, Ts ₁ To Ts _Three In the sustain (lighting) period up to the above, the luminance is controlled according to the length of the total lighting time within one frame period by controlling the EL element to be in a lighting state or not. In this example, as shown in FIG. 9B, the combination of the sustain (lighting) periods to be lit is 2 ^Three Since eight lighting times can be determined, eight gradations from 0 (all black display) to 7 (all white display) can be displayed. In the time gradation method, gradation expression is performed as described above. Needless to say, the same gradation expression is possible in a self-luminous device for color display.
[0017]
When the number of gradations is further increased, the number of divisions in one frame period may be increased. When one frame period is divided into n subframes, the ratio of the length of the sustain (lighting) period is Ts. ₁ : Ts ₂ : Ts _(n-1) : Ts _n = 2 ^(n-1) : 2 ^(n-2) : 2 ¹ : 2 ⁰ 2 ⁿ It is possible to express street gradation. The order of the subframe periods is SF ₁ ~ SF _n You may make it appear randomly.
[0018]
[Problems to be solved by the invention]
By the way, problems relating to a self-luminous device using a self-luminous element such as an EL element will be described. As described above, during the period in which the EL element is lit, current is always supplied, and current flows in the EL element. Thereby, the property of the EL element itself deteriorates due to long-time lighting, and the luminance characteristic changes due to this deterioration. That is, even if the EL element that has deteriorated and the EL element that has not deteriorated are supplied with the same voltage from the same current supply source, a difference in luminance occurs.
[0019]
A specific example will be described. FIG. 10A shows a display screen of a portable terminal device or the like using the self-light-emitting device, and an operation icon 1001 is displayed. Usually, in the use of such a device, the ratio of still image display as shown in FIG. At this time, if an icon or the like is displayed in a color (gradation) brighter than the background, the EL element in the pixel where the icon or the like is displayed lights for a longer time than the EL element in the background display part. Therefore, deterioration progresses faster.
[0020]
It is assumed that the deterioration of the EL element proceeds under such conditions. Display examples of the self-luminous device after deterioration are shown in FIGS. First, in the case of black display as shown in FIG. 10B, the self-luminous element such as the EL element expresses black when no voltage is applied to the element. Degradation is unlikely to be a problem at that time. However, in the case of white display, even if the same current is supplied to the EL element deteriorated by lighting for a long time (in this case, the EL element where the icon or the like was displayed), FIG. As indicated by reference numeral 1011, the luminance is insufficient and unevenness occurs.
[0021]
In order to solve this luminance unevenness, there is a method of increasing the voltage applied to the deteriorated EL element. Usually, in the self-luminous device, the current supply line is composed of a single wiring, and is arranged in a matrix. It is not easy to configure a circuit for changing a voltage applied to an EL element in one specific pixel in the pixel portion. Further, as described above, since there are variations in EL driving TFTs, such a correction method is not desirable.
[0022]
Further, in a self-light emitting device for color display, the brightness and the degree of deterioration may vary depending on the elements that display R, G, and B. Several methods have been proposed for correcting the luminance variation due to such a cause. However, even the pixels of the same color may be deteriorated and the luminance variation may occur. In such a case, the above method cannot be used. .
[0023]
As another method for solving the problem, a method of using an EL element having characteristics capable of withstanding long-time lighting may be considered, but the current life of the EL element is not sufficient. Accordingly, it is an object of the present invention to provide a self-light-emitting device capable of normal video display without luminance unevenness even when the elements in the screen are deteriorated.
[0024]
[Means for Solving the Problems]
In order to solve the above-described problems, the following measures are taken in the present invention.
[0025]
In the self-light-emitting device having the deterioration correction function of the present invention, the lighting time of each pixel or the lighting time and the lighting intensity is detected by periodically sampling the video signal, The video signal for driving the deteriorated pixel of the EL element is corrected each time with reference to the data of the luminance characteristics of the EL element stored in advance, and the EL elements in some pixels deteriorate. Even in the self-luminous device, the uniformity of the screen can be maintained without causing luminance unevenness.
[0026]
Below, the structure of the self-light-emitting device of this invention is described.
[0027]
The self-luminous device of the present invention according to claim 1 comprises:
In a self-luminous device that displays video by inputting video signals,
Means for detecting the cumulative lighting time of each pixel;
Means for storing the cumulative lighting time;
Means for correcting the video signal according to the stored cumulative lighting time,
A video is displayed using the corrected video signal.
[0028]
The self-light-emitting device of the present invention according to claim 2
In a self-luminous device that displays video by inputting video signals,
Means for detecting the cumulative lighting time and lighting intensity of each pixel;
Means for storing the cumulative lighting time and lighting intensity;
Means for correcting the video signal according to the stored cumulative lighting time and lighting intensity,
A video is displayed using the corrected video signal.
[0029]
The self-luminous device of the present invention according to claim 3
In a self-luminous device that displays video by inputting video signals,
A counter unit that samples the first video signal and periodically detects the lighting time of the light-emitting element of each pixel;
A storage circuit for accumulating and storing lighting times of the self-luminous elements of the respective pixels detected by the counter unit;
A signal correction unit that corrects the first video signal according to the cumulative lighting time of the self-light-emitting element of each pixel stored in the storage circuit and outputs a second video signal;
A deterioration correction device having
A display device for displaying an image by the second image signal in the previous period;
It is characterized by having.
[0030]
The self-luminous device of the present invention according to claim 4
In a self-luminous device that displays video by inputting video signals,
A counter unit that samples the first video signal and periodically detects the lighting time and the lighting intensity of each pixel;
A storage circuit for accumulating and storing lighting times and lighting intensities of the light-emitting elements of the respective pixels detected by the counter unit;
Signal correction for correcting the first video signal and outputting the second video signal according to the cumulative lighting time and lighting intensity of the self-luminous element of each pixel accumulated and stored in the storage circuit And
A deterioration correction device having
A display device for displaying an image by the second image signal in the previous period;
It is characterized by having.
[0031]
The self-luminous device of the present invention according to claim 5 is:
The self light-emitting device according to any one of claims 1 to 4,
A self-luminous device that performs n-bit (n is a natural number, n ≧ 2) gradation display has a driving circuit that performs n + m-bit (m is a natural number) signal processing,
A video signal written in a pixel having a self-luminous element that has not deteriorated is displayed in gradation by an n-bit video signal,
For the video signal written in the pixel having the degraded self-luminous element, the gradation is corrected using an m-bit signal,
It is characterized in that the same luminance is obtained between the self-luminous element that has not deteriorated and the self-luminous element that has deteriorated.
[0032]
The self-light-emitting device of the present invention according to claim 6 comprises:
The self light-emitting device according to any one of claims 1 to 4,
The video signal written in the pixel having the degraded self-luminous element is characterized by relatively performing addition processing on the video signal written in the pixel having the non-degraded self-luminous element.
[0033]
The self-light-emitting device of the present invention according to claim 7 comprises:
The self light-emitting device according to any one of claims 1 to 4,
In a display range, a video signal written to a pixel having a self-luminous element with little degradation or a pixel having a self-luminous element that has not deteriorated is a video signal written to a pixel having a self-luminous element having the greatest degradation. On the other hand, it is characterized by relatively performing a subtraction process.
[0034]
The self-luminous device of the present invention according to claim 8 is,
The self light-emitting device according to any one of claims 1 to 7,
The storage means or the storage circuit is a static storage circuit (SRAM).
[0035]
The self-luminous device of the present invention according to claim 9 is,
The self light-emitting device according to any one of claims 1 to 7,
The storage means or the storage circuit is a dynamic storage circuit (DRAM).
[0036]
The self-luminous device of the present invention according to claim 10
The self light-emitting device according to any one of claims 1 to 7,
The storage means or storage circuit is a ferroelectric storage circuit (FeRAM).
[0037]
The self-luminous device of the present invention according to claim 11
The self light-emitting device according to any one of claims 1 to 7,
The storage means or the storage circuit is a nonvolatile memory (EEPROM) that can be electrically written, read and erased.
[0038]
The self-luminous device of the present invention according to claim 12
The self light-emitting device according to claim 1 or 2,
The detection unit, the storage unit, and the correction unit are configured by a circuit outside the self-light-emitting device.
[0039]
The self-luminous device of the present invention according to claim 13
The self light-emitting device according to claim 1 or 2,
The detection means, the storage means, and the correction means are formed on the same insulator as the self-light-emitting device.
[0040]
The self-luminous device of the present invention according to claim 14 comprises:
The self light-emitting device according to claim 3, wherein
The counter unit, the storage circuit, and the signal correction unit are configured by circuits outside the self-light-emitting device.
[0041]
The self-luminous device of the present invention according to claim 15 comprises:
The self light-emitting device according to claim 3, wherein
The counter unit, the memory circuit, and the signal correction unit are formed on the same insulator as the self-light-emitting device.
[0042]
The self-luminous device of the present invention according to claim 16 comprises:
The self light-emitting device according to any one of claims 1 to 15,
The self-luminous device is an EL display.
[0043]
The self-luminous device of the present invention according to claim 17 comprises:
The self light-emitting device according to any one of claims 1 to 15,
The self-luminous device is a PDP display.
[0044]
The self-luminous device of the present invention according to claim 18
The self light-emitting device according to any one of claims 1 to 15,
The self-luminous device is an FED display.
[0045]
The driving method of the self-luminous device of the present invention according to claim 19
A driving method of a self-light-emitting device that inputs a video signal and displays a video,
The first video signal is sampled, and the lighting time of the self-luminous element of each pixel is periodically detected in the counter unit,
The lighting time of the self-luminous element of each pixel detected by the counter unit is accumulated and stored in a storage circuit,
The signal correction unit corrects the first video signal and outputs a second video signal according to the cumulative lighting time of the self-luminous element of each pixel accumulated and stored in the storage circuit,
The video is displayed by the second video signal in the previous period.
[0046]
The driving method of the self-luminous device of the present invention according to claim 20 comprises:
A driving method of a self-light-emitting device that inputs a video signal and displays a video,
Sampling the first video signal, and periodically detecting the lighting time and lighting intensity of the light-emitting element of each pixel in the counter unit,
The lighting time and lighting intensity of the light-emitting element of each pixel detected by the counter unit are accumulated and stored in a storage circuit,
In accordance with the cumulative lighting time and lighting intensity of the light-emitting elements of the respective pixels accumulated and stored in the storage circuit, the signal correction unit corrects the first video signal to obtain the second video signal. Output,
The video is displayed by the second video signal in the previous period.
[0047]
The driving method of the self-luminous device of the present invention according to claim 21 comprises:
In the driving method of the self light-emitting device according to claim 19 or 20,
A self-luminous device that performs n-bit (n is a natural number, n ≧ 2) gradation display has a driving circuit that performs n + m-bit (m is a natural number) signal processing,
A video signal written in a pixel having a self-luminous element that has not deteriorated is displayed in gradation by an n-bit video signal,
For the video signal written in the pixel having the degraded self-luminous element, the gradation is corrected using an m-bit signal,
It is characterized in that the same luminance is obtained between the self-luminous element that has not deteriorated and the self-luminous element that has deteriorated.
[0048]
According to a twenty-second aspect of the present invention, there is provided a self-luminous device driving method according to
The self light-emitting device according to any one of claims 19 to 21,
The video signal written in the pixel having the degraded self-luminous element is characterized by relatively performing addition processing on the video signal written in the pixel having the non-degraded self-luminous element.
[0049]
The driving method of the self-luminous device of the present invention according to claim 23,
The self light-emitting device according to any one of claims 19 to 21,
In a display range, a video signal written to a pixel having a self-luminous element with little degradation or a pixel having a self-luminous element that has not deteriorated is a video signal written to a pixel having a self-luminous element having the greatest degradation. On the other hand, it is characterized by relatively performing a subtraction process.
[0050]
DETAILED DESCRIPTION OF THE INVENTION
Please refer to FIG. FIG. 1 shows a block diagram of a self-luminous device having a deterioration correction function of the present invention. The deterioration correction apparatus that is the basis of the present invention includes I: a counter unit, II: a memory circuit unit, and III: a signal correction unit. I has a counter 102, II has a volatile memory 103 and a non-volatile memory 104, and III has a correction circuit 105 and a correction data storage unit 106.
[0051]
A circuit diagram of a source signal line driver circuit in the display device 107 is illustrated in FIG. Here, a display device corresponding to a digital video signal is taken as an example. The source signal line driver circuit includes a shift register (SR) 1401, a first latch circuit (LAT1) 1402, a second latch circuit (LAT2) 1403, and the like. Reference numeral 1404 denotes a pixel, and 1405 denotes the deterioration correction apparatus shown in FIG.
[0052]
The operation of each part will be described. Sampling pulses are sequentially output from the shift register according to the clock signal (CLK) and the start pulse (SP). The first latch circuit holds the digital video signal according to the timing of the sampling pulse. As shown in FIG. 14A, at this time, the video signal has already been corrected and becomes the second video signal. When the first latch circuit finishes holding for one horizontal period, a latch pulse is output and a digital video signal is transferred to the second latch circuit. After that, writing to the pixel is performed from the second latch circuit. At the same time, the digital video signal is held in the first latch circuit again according to the sampling pulse from the shift register.
[0053]
Subsequently, the operation of the entire deterioration correction apparatus will be described. First, with respect to the EL elements used in the self-light-emitting device, the data of the change over time of the luminance characteristics is stored in advance in the correction data storage unit 106. As will be described later, this data is mainly used as a map for signal correction according to the degree of deterioration of the EL element of each pixel.
[0054]
Subsequently, the first video signal 101A is sampled periodically (for example, every second), and the counter 102 counts lighting and non-lighting in each pixel based on the signal. The number of times of lighting in each pixel counted here is sequentially stored in the memory circuit unit. Here, since the number of times of lighting is accumulated, it is preferable that the memory circuit is configured using a nonvolatile memory. However, since the number of times of writing is generally limited in the nonvolatile memory, FIG. As shown in the figure, the volatile memory 103 is used for storage during the operation of the self-light-emitting device, and data is written into the nonvolatile memory 104 at regular intervals (for example, every hour or when the power is shut down). .
[0055]
Further, when gradation expression using EL elements is also performed by luminance control, the lighting intensity of the EL elements at that time is detected together, and the deterioration state is determined from both the lighting time and the lighting intensity. good. In this case, correction data is also created accordingly.
[0056]
Examples of the memory used for the memory circuit include static memory (SRAM), dynamic memory (DRAM), ferroelectric memory (FeRAM), EEPROM, flash memory, and the like. What is necessary is just to comprise using what is generally used. However, when a DRAM is used as the volatile memory, it is necessary to add a periodic refresh function.
[0057]
Next, the operation proceeds to a video signal correction operation. Refer to FIG. 1 again. The correction circuit 105 receives the first video signal 101A and the accumulated lighting time of each pixel or the data of the accumulated lighting time and the lighting intensity. The correction circuit 105 refers to the video signal correction map stored in the correction data storage unit in advance and the cumulative lighting time of each pixel, or the cumulative lighting time and lighting intensity, and matches the degree of deterioration of each pixel. The input video signal is corrected. The second video signal 101B corrected in this way is input to the display device 107 to display an image.
[0058]
At power-off, the cumulative lighting time or cumulative lighting time and lighting intensity of the EL elements of each pixel stored in the volatile memory circuit is the cumulative lighting time or cumulative lighting stored in the nonvolatile memory circuit. Add to time and lighting intensity and store. Thereby, after the next power-on, the lighting time of the EL element or the cumulative counting of the lighting time and the lighting intensity is continuously performed.
[0059]
As described above, the lighting time of the EL element is periodically detected, and the accumulated lighting time or the accumulated lighting time and the lighting intensity are stored, so that the luminance characteristics of the EL element stored in advance are stored over time. With reference to the change data, the video signal is corrected each time, and the video signal can be corrected so that the deteriorated EL element can achieve the same luminance as that of the non-deteriorated EL element. Therefore, the uniformity of the screen can be maintained without causing luminance unevenness.
[0060]
Further, according to the correction method used in the self-light-emitting device of the present invention, since the user does not need to perform an operation, the product can be expected to have a long life by continuing the correction even after the end user. .
[0061]
In the above, the self-light-emitting device has been described as an example using an EL element. However, the self-light-emitting device of the present invention is not limited to EL and may be other self-light-emitting devices such as PDP and FED.
【Example】
Examples of the present invention will be described below.
[0062]
[Example 1]
In this embodiment, a digital video signal correction method in the signal correction unit will be described.
[0063]
As one of the methods of complementing the luminance of the deteriorated EL element at the signal level, the correction value existing in the input digital video signal is added and converted into a signal of several gradations, so that A method for achieving the same luminance is mentioned. In order to realize this most simply by circuit design, it is sufficient to prepare in advance a circuit capable of processing the added gradation. Specifically, for example, in the case of a 6-bit digital gradation (64 gradation) specification self-luminous device having the deterioration correction function of the present invention, a processing capability for 1 bit is added as an extra for correction, Designed and created as a real 7-bit digital gradation (128 gradations). In normal operation, the lower 6 bits are used, and when the EL element deteriorates, it is corrected to a normal digital video signal. The values are added, and signal processing for the addition is performed using the above-described 1 bit for addition. In this case, the most significant bit (MSB) is used only for signal correction, and the actual display gradation is 6 bits.
[0064]
In addition, when the upper bits are used for correction, it is not particularly necessary to use the most significant bit. That is, when normal display is performed with 6 bits, the operation is the same even if a drive circuit having a processing capability of 8 bits or more is used.
[Example 2]
In this embodiment, a digital video signal correction method different from that in the first embodiment will be described.
[0065]
Please refer to FIG. 1 and FIG. FIG. 2A illustrates part of the pixels of the display device 107 in FIG. Here, three pixels 201 to 203 are considered. First, it is assumed that the pixel 201 is a pixel that has not deteriorated, and that both the pixels 202 and 203 have deteriorated to some extent. At this time, if the degree of deterioration is larger in the pixel 203 than in the pixel 202, naturally, a decrease in luminance due to the deterioration also increases. That is, when a certain halftone is displayed, luminance unevenness occurs as shown in FIG. The luminance of the pixel 202 is lower than the luminance of the pixel 201, and further the luminance of the pixel 203 is lower.
[0066]
Next, an actual correction operation will be described. The relationship between the lighting time of the EL element or the lighting time and lighting intensity and the luminance drop due to deterioration is measured in advance, and a map in which a correction amount for the cumulative lighting time is set is prepared and stored in the correction data storage unit 106. Keep it. An example is shown in FIG. The number in the block indicated by 200 represents the correction amount of the digital video signal. In other words, 1 is always added to the digital video signal input to the pixel in which the deterioration of the EL element is accumulated up to stage a, and the signal is corrected to be brighter by one gradation. Similarly, correction of two gradations is applied at the stage b and three gradations are applied at the stage c. The cumulative lighting time or the cumulative lighting time, the lighting intensity, and the luminance decrease due to deterioration may not necessarily be in a direct proportional relationship, and the correction width of the video signal is approximated in steps for each gradation.
[0067]
In FIG. 1, the correction circuit 105 inputs a digital video signal (first video signal) 101 </ b> A and reads the accumulated lighting time of each pixel stored in the storage circuit unit. The correction value of each digital video signal is determined by comparing the accumulated lighting time of each read pixel or the cumulative lighting time and the lighting intensity with the correction map described above. Specifically, using FIG. 2A, it is determined that the pixel 201 has not deteriorated from the accumulated lighting time or the accumulated lighting time and the lighting intensity, and the video signal is not corrected. When it is determined that the pixel 202 has deteriorated to the stage a in FIG. 2B, the digital video signal for lighting the pixel 202 includes +1 gradation as shown in FIG. Correction by the addition process is added. Similarly, when the pixel 203 is determined to have deteriorated to the stage b, the digital video signal for lighting the pixel 203 is corrected by the addition process of +2 gradation. As described above, a screen with uniform brightness can be obtained as shown in FIG.
[0068]
Subsequently, a correction method by subtraction processing will be described. Please refer to FIG. 1 and FIG. Since FIGS. 3A to 3C are the same as FIGS. 2A to 2C, description thereof is omitted here.
[0069]
The correction value of each digital video signal is determined by comparing the accumulated lighting time in each pixel or the accumulated lighting time and the lighting intensity with the map in which the correction amount shown in FIG. 3C is set. At this time, the reference pixel, that is, the pixel to which the original digital video signal is input as it is without correction is determined to have the most advanced deterioration from the accumulated lighting time or the accumulated lighting time and the lighting intensity. Pixel. Specifically, the pixel 303 in FIG. With this as a reference, digital video signals input to other pixels are corrected according to the degree of deterioration. As shown in FIG. 3D, the original digital video signal is input to the pixel 303 that has been most deteriorated (assuming that it has advanced to the stage b in FIG. 3C). In addition, a digital video signal to which correction of -1 gradation is applied is input to the pixel 302, which is lightly degraded by one level (assuming that the level has progressed to level a in FIG. 3C). A digital video signal to which correction of −2 gradation is added is input to the pixel 301 that is determined not to have deteriorated from the lighting time or the cumulative lighting time and the lighting intensity.
[0070]
However, when the correction is performed by the above-described means, the luminance of the entire screen is several gradations (the gradation based on the original digital video signal and the gradation based on the second video signal written in the pixel in which the EL element has not deteriorated). Will be reduced by the difference). Therefore, at the same time, as shown in FIG. 3D, by changing the potential of the current supply line, the voltage V between the two electrodes of the EL element is changed. _EL I will make it slightly higher (V _EL1 + Δ → V _EL2 ) To complement the brightness of the entire screen.
[0071]
In the case of correction by the former addition processing, luminance unevenness can be corrected only by processing of the digital video signal, but correction in white display does not work (specifically, for example, as a 6-bit digital video signal, When “111111” is input, there is a disadvantage that no further addition is possible. In addition, in the case of the correction by the latter subtraction processing, potential control of the current supply line for luminance complementation is added, but contrary to the correction by the addition processing, the non-correction range is a black display range, and therefore almost all There is no influence (specifically, for example, when “000000” is input as a 6-bit digital video signal, there is no need to perform further subtraction, and there is no need to perform accurate subtraction between a normal EL element and a deteriorated EL element. It is possible to display black (the EL element can be simply turned off), and several gradations in the vicinity of black are hardly a problem if the number of corresponding bits of the display device is high to some extent. Both are advantageous methods for increasing the number of gradations.
[0072]
Further, for example, it can be said that it is also an effective means to compensate for both disadvantages by using both correction methods of addition processing and subtraction processing together with a certain gradation as a boundary.
[0073]
[Example 3]
In the self-light-emitting device having the deterioration correction function of the present invention, in the example shown in the embodiment (FIG. 1), the deterioration correction device is placed outside the display device 107, and a digital video signal (first video signal) 101A. First, it is input to the correction circuit 105 and immediately corrected, and the corrected digital video signal (second video signal) 101B is input to the display device 107 via the FPC. Advantages of such a method include compatibility by unitizing the deterioration correction device (the conventional self-light-emitting device can be used as the display device 107 as it is), but on the other hand, the deterioration correction device and the display device Are integrally formed on the same substrate, so that cost reduction, space saving, and high-speed driving can be realized by greatly reducing the number of components.
[0074]
FIG. 4A shows an example in which the deterioration correcting device is integrally formed on the same substrate as the display device in the self light emitting device having the deterioration correcting function of the present invention. A display device including a source signal line driver circuit 402, a gate signal line driver circuit 403, a pixel portion 404, a current supply line 405, and an FPC 406 and a deterioration correction device 407 are integrally formed over the substrate 401. FIG. 4B is an example of an internal block diagram of the deterioration correction apparatus 407 in FIG. Of course, the layout on the substrate is not limited to the example shown in the figure, but it is desirable to arrange the blocks close to each other in consideration of the arrangement of signal lines and the wiring length.
[0075]
The digital video signal (first video signal) 411A is input from an external video source to the correction circuit 415 in the deterioration correction device 407 via the FPC 406. After that, a corrected digital video signal (second video signal) 411B that has been corrected by the method described in the embodiment and Examples 1-2 is input to the source signal line driver circuit 402.
[0076]
Although not shown in FIG. 4, a necessary control signal may be input to the deterioration correction apparatus. In the example shown in FIG. 4A, the deterioration correction device 407 is arranged between the FPC 406 and the source signal line driver circuit 402, so that the control signal can be easily routed.
[0077]
[Example 4]
Please refer to FIG. The self-light-emitting device having the deterioration correction function of the present invention can be easily applied even when the display device is compatible with an analog video signal. In such a case, the second video signal (digital video signal) output from the deterioration correction device including I: counter unit, II: storage circuit unit, and III: signal correction unit is the D / A conversion circuit 1307. Is converted into an analog video signal and input to the display device 1308 corresponding to the analog video signal to display an image.
[0078]
A circuit diagram of a source signal line driver circuit in the display device 1308 in FIG. 13 is shown in FIG. Here, a display device corresponding to an analog video signal is taken as an example. The source signal line driver circuit includes a shift register (SR) 1411, a level shifter 1412, a buffer 1413, a sampling switch 1414, and the like. Reference numeral 1415 denotes a pixel, 1416 denotes a deterioration correction apparatus shown in FIG. 13, and 1417 denotes a D / A conversion circuit.
[0079]
The operation of each part will be described. Sampling pulses are sequentially output from the shift register according to the clock signal (CLK) and the start pulse (SP). Thereafter, the voltage amplitude of the pulse is expanded by the level shifter and output via the buffer. The digital video signal is corrected by the deterioration correction device, converted into an analog video signal by the D / A conversion circuit, and input to the video signal line. Thereafter, the sampling switch is opened according to the timing of the sampling pulse, the analog video signal inputted to the video signal line is sampled, and the voltage information is written in the pixel to display the image.
[0080]
In the example shown in FIG. 13, the deterioration correction device is provided outside the display device. However, as described in the third embodiment, these may be integrally formed on the same substrate.
[0081]
[Example 5]
In this embodiment, the TFTs of the pixel portion of the self-light-emitting device of the present invention and the drive circuit portion (source signal line side drive circuit, gate signal line side drive circuit, pixel selection signal line side drive circuit) provided in the periphery thereof are simultaneously A manufacturing method will be described. However, in order to simplify the description, a CMOS circuit which is a basic unit is illustrated in the drive circuit portion.
[0082]
Reference is made to FIG. First, in this embodiment, a substrate 5000 made of glass such as barium borosilicate glass represented by Corning # 7059 glass or # 1737 glass or aluminoborosilicate glass is used. Note that the substrate 5000 is not limited as long as it is a light-transmitting substrate, and a quartz substrate may be used. Further, a plastic substrate having heat resistance that can withstand the processing temperature of this embodiment may be used.
[0083]
Next, a base film 5001 made of an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon oxynitride film is formed over the substrate 5000. In this embodiment, a two-layer structure is used as the base film 5001, but a single-layer film of the insulating film or a structure in which two or more layers are stacked may be used. As the first layer of the base film 5001, a plasma CVD method is used, and SiH _Four , NH _Three And N ₂ A silicon oxynitride film 5001a formed using O as a reactive gas is formed to 10 to 200 [nm] (preferably 50 to 100 [nm]). In this embodiment, a silicon oxynitride film 5001a (composition ratio Si = 32 [%], O = 27 [%], N = 24 [%], H = 17 [%]) having a thickness of 50 [nm] is formed. did. Next, as the second layer of the base film 5001, a plasma CVD method is used, and SiH _Four And N ₂ A silicon oxynitride film 5001b formed using O as a reactive gas is formed to a thickness of 50 to 200 [nm] (preferably 100 to 150 [nm]). In this embodiment, a silicon oxynitride film 5001b (composition ratio Si = 32 [%], O = 59 [%], N = 7 [%], H = 2 [%]) having a thickness of 100 [nm] is formed. did.
[0084]
Next, semiconductor layers 5002 to 5005 are formed over the base film. The semiconductor layers 5002 to 5005 are formed by forming a semiconductor film having an amorphous structure by a known means (sputtering method, LPCVD method, plasma CVD method, or the like), and then performing a known crystallization process (laser crystallization method, heat A crystalline semiconductor film obtained by performing a crystallization method or a thermal crystallization method using a catalyst such as nickel) is formed by patterning into a desired shape. The semiconductor layers 5002 to 5005 are formed with a thickness of 25 to 80 [nm] (preferably 30 to 60 [nm]). The material of the crystalline semiconductor film is not limited, but is preferably silicon (silicon) or silicon germanium (Si _X Ge _1-X (X = 0.0001 to 0.02)) It may be formed of an alloy or the like. In this embodiment, a 55 nm thick amorphous silicon film was formed by plasma CVD, and then a solution containing nickel was held on the amorphous silicon film. This amorphous silicon film is dehydrogenated (500 [° C.], 1 hour), then subjected to thermal crystallization (550 [° C.], 4 hours) to further improve the crystallization by laser annealing. A crystalline silicon film was formed by performing the above-described treatment. Then, semiconductor layers 5002 to 5005 were formed from the crystalline silicon film by patterning using a photolithography method.
[0085]
Further, after the semiconductor layers 5002 to 5005 are formed, a small amount of impurity element (boron or phosphorus) may be doped in order to control the threshold value of the TFT.
[0086]
When a crystalline semiconductor film is formed by laser crystallization, a pulse oscillation type or continuous emission type excimer laser, YAG laser, YVO _Four A laser can be used. When these lasers are used, it is preferable to use a method in which laser light emitted from a laser oscillator is linearly collected by an optical system and irradiated onto a semiconductor film. The conditions for crystallization are appropriately selected by the practitioner. When an excimer laser is used, the pulse oscillation frequency is 30 [Hz] and the laser energy density is 100 to 400 [mJ / cm. ² ] (Typically 200-300 [mJ / cm ² ]). When a YAG laser is used, the second harmonic is used and the pulse oscillation frequency is 1 to 10 kHz, and the laser energy density is 300 to 600 [mJ / cm. ² ] (Typically 350-500 [mJ / cm ² ]) Then, a laser beam condensed in a linear shape with a width of 100 to 1000 [μm], for example, 400 [μm] is irradiated over the entire surface of the substrate, and the superposition ratio (overlap ratio) of the linear laser light at this time is 50. What is necessary is just to carry out as ~ 90 [%].
[0087]
Next, a gate insulating film 5006 is formed to cover the semiconductor layers 5002 to 5005. The gate insulating film 5006 is formed of an insulating film containing silicon with a thickness of 40 to 150 [nm] by using a plasma CVD method or a sputtering method. In this embodiment, a silicon oxynitride film (composition ratio Si = 32 [%], O = 59 [%], N = 7 [%], H = 2 [%] with a thickness of 110 [nm] by plasma CVD. ]). Needless to say, the gate insulating film is not limited to the silicon oxynitride film, and another insulating film containing silicon may be used as a single layer or a stacked structure.
[0088]
When a silicon oxide film is used, TEOS (Tetraethyl Orthosilicate) and O ₂ And a reaction pressure of 40 [Pa], a substrate temperature of 300 to 400 [° C.], a high frequency (13.56 [MHz]) power density of 0.5 to 0.8 [W / cm]. ₂ ] Can be formed by discharging. The silicon oxide film thus produced can obtain good characteristics as a gate insulating film by subsequent thermal annealing at 400 to 500 [° C.].
[0089]
Next, a first conductive film 5007 with a thickness of 20 to 100 [nm] and a second conductive film 5008 with a thickness of 100 to 400 [nm] are stacked over the gate insulating film 5006. In this example, a first conductive film 5007 made of a TaN film with a thickness of 30 [nm] and a second conductive film 5008 made of a W film with a thickness of 370 [nm] were stacked. The TaN film was formed by sputtering, and was sputtered in a nitrogen-containing atmosphere using a Ta target. The W film was formed by sputtering using a W target. In addition, tungsten hexafluoride (WF ₆ It is also possible to form it by a thermal CVD method using). In any case, in order to use as a gate electrode, it is necessary to reduce the resistance, and it is desirable that the resistivity of the W film be 20 [μΩcm] or less. The resistivity of the W film can be reduced by increasing the crystal grains. However, when there are many impurity elements such as oxygen in the W film, the crystallization is hindered and the resistance is increased. Therefore, in this embodiment, a sputtering method using a target of high purity W (purity 99.9999 [%]) is used, and the W film is sufficiently considered so that impurities are not mixed in the gas phase during film formation. It was possible to realize a resistivity of 9 to 20 [μΩcm].
[0090]
Note that in this embodiment, the first conductive film 5007 is TaN and the second conductive film 5008 is W, but there is no particular limitation, and all of them are Ta, W, Ti, Mo, Al, Cu, Cr, Nd. You may form with the element selected from these, or the alloy material or compound material which has the said element as a main component. Alternatively, a semiconductor film typified by a polycrystalline silicon film doped with an impurity element such as phosphorus may be used. Moreover, you may use the alloy which consists of Ag, Pd, and Cu. Also, a combination in which the first conductive film is formed of a Ta film, the second conductive film is a W film, the first conductive film is formed of a TiN film, and the second conductive film is a W film, The first conductive film is formed of a tantalum nitride (TaN) film, the second conductive film is an Al film, the first conductive film is formed of a TaN film, and the second conductive film is a Cu film. It is good also as a combination.
[0091]
Next, as shown in FIG. 5B, a resist mask 5009 is formed by photolithography, and a first etching process for forming electrodes and wirings is performed. The first etching process is performed under the first and second etching conditions. In this embodiment, ICP (Inductively Coupled Plasma) etching method is used as the first etching condition, and CF is used as an etching gas. _Four And Cl ₂ And O ₂ The gas flow ratio is 25/25/10 [sccm], and 500 [W] RF (13.56 [MHz]) power is applied to the coil-type electrode at a pressure of 1 [Pa]. Etching was performed by generating plasma. Here, a dry etching apparatus (Model E645- □ ICP) using ICP manufactured by Matsushita Electric Industrial Co., Ltd. was used. 150 [W] RF (13.56 [MHz]) power is also applied to the substrate side (sample stage), and a substantially negative self-bias voltage is applied. The W film is etched under this first etching condition so that the end portion of the first conductive layer is tapered. Under the first etching conditions, the etching rate with respect to W is 200.39 [nm / min.], The etching rate with respect to TaN is 80.32 [nm / min.], And the selectivity of W with respect to TaN is about 2.5. It is. Further, the taper angle of W is about 26 ° under this first etching condition.
[0092]
After that, as shown in FIG. 5B, the resist mask 5009 is not removed and the second etching condition is changed, and the etching gas is changed to CF. _Four And Cl ₂ Each gas flow rate ratio is 30/30 [sccm], and 500 [W] RF (13.56 [MHz]) power is applied to the coil-type electrode at a pressure of 1 [Pa] to generate plasma. And etching was performed for about 30 seconds. 20 [W] RF (13.56 [MHz]) power is also applied to the substrate side (sample stage), and a substantially negative self-bias voltage is applied. CF _Four And Cl ₂ Under the second etching condition in which is mixed, the W film and the TaN film are etched to the same extent. The etching rate for W under the second etching conditions is 58.97 [nm / min.], And the etching rate for TaN is 66.43 [nm / min.]. Note that in order to perform etching without leaving any residue on the gate insulating film, it is preferable to increase the etching time at a rate of about 10 to 20%.
[0093]
In the first etching process, the shape of the mask made of resist is made suitable, and the end portions of the first conductive layer and the second conductive layer are tapered due to the effect of the bias voltage applied to the substrate side. It becomes. The angle of the tapered portion may be 15 to 45 °. Thus, the first shape conductive layers 5010 to 5014 (the first conductive layers 5010a to 5014a and the second conductive layers 5010b to 5014b) formed of the first conductive layer and the second conductive layer by the first etching process. Form. In the gate insulating film 5006, a region that is not covered with the first shape conductive layers 5010 to 5014 is etched and thinned by about 20 to 50 [nm].
[0094]
Then, a first doping process is performed without removing the resist mask, and an impurity element imparting n-type conductivity is added to the semiconductor layer (FIG. 5B). The doping process may be performed by ion doping or ion implantation. The condition of the ion doping method is a dose of 1 × 10 ¹³ ~ 5x10 ¹⁵ [atoms / cm ² The acceleration voltage is set to 60 to 100 [keV]. In this embodiment, the dose is 1.5 × 10 ¹⁵ [atoms / cm ² The acceleration voltage was 80 [keV]. As an impurity element imparting n-type, an element belonging to Group 15, typically phosphorus (P) or arsenic (As), is used here, but phosphorus (P) is used. In this case, the first shape conductive layers 5010 to 5014 serve as a mask for the impurity element imparting n-type, and high-concentration impurity regions 5015 to 5018 are formed in a self-aligning manner. The high concentration impurity regions 5015 to 5018 have 1 × 10 ²⁰ ~ 1x10 ^{twenty one} [atoms / cm ^Three An impurity element imparting n-type is added in a concentration range of
[0095]
Next, as shown in FIG. 5C, a second etching process is performed without removing the resist mask. Here, CF is used as an etching gas. _Four And Cl ₂ And O ₂ The gas flow ratio is 20/20/20 [sccm], and 500 [W] RF (13.56 [MHz]) power is applied to the coil-type electrode at a pressure of 1 [Pa]. Etching was performed by generating plasma. 20 [W] RF (13.56 [MHz]) power is also applied to the substrate side (sample stage), and a substantially negative self-bias voltage is applied. The etching rate for W in the second etching process is 124. [nm / min.], the etching rate for TaN is 20. [nm / min.], and the selection ratio of W to TaN is 6.05. Therefore, the W film is selectively etched. By this second etching, the taper angle of W became 70 °. By this second etching process, second conductive layers 5019b to 5023b are formed. On the other hand, the first conductive layers 5010a to 5014a are hardly etched, and the first conductive layers 5019a to 5023a are formed.
[0096]
Next, a second doping process is performed. Doping is performed using the second conductive layers 5019b to 5023b as masks against the impurity element so that the impurity element is added to the semiconductor layer below the tapered portion of the first conductive layer. In this embodiment, P (phosphorus) is used as the impurity element, and the dose amount is 1.5 × 10. ¹⁴ [atoms / cm ² The plasma doping was performed at a current density of 0.5 [μA] and an acceleration voltage of 90 [keV]. In this manner, low concentration impurity regions 329 to 333 overlapping with the first conductive layer are formed in a self-aligning manner. The concentration of phosphorus (P) added to the low-concentration impurity regions 5024 to 5027 is 1 × 10 17 to 5 × 10 18 [atoms / cm ^Three And has a gradual concentration gradient according to the thickness of the tapered portion of the first conductive layer. Note that in the semiconductor layer overlapping the tapered portion of the first conductive layer, the impurity concentration is slightly lower from the end of the tapered portion of the first conductive layer to the inside, but the concentration is almost the same. . An impurity element is also added to the high-concentration impurity regions 5015 to 5018 (FIG. 6A).
[0097]
Next, as shown in FIG. 6B, a resist mask is removed, and then a third etching process is performed using a photolithography method. In the third etching process, the tapered portion of the first conductive layer is partially etched to form a shape overlapping the second conductive layer. However, a mask made of a resist 5028 is formed in a region where the third etching is not performed.
[0098]
The etching conditions in the third etching process are Cl as an etching gas. ₂ And SF ₆ And the respective gas flow ratios are set to 10/50 [sccm], using the ICP etching method in the same manner as the first and second etchings. The etching rate for TaN in the third etching process is 111.2 [nm / min.], And the etching rate for the gate insulating film is 12.8 [nm / min.].
[0099]
In this example, etching was performed by generating plasma by applying 500 [W] RF (13.56 [MHz]) power to the coil-type electrode at a pressure of 1.3 [Pa]. 10 [W] RF (13.56 [MHz]) power is also applied to the substrate side (sample stage), and a substantially negative self-bias voltage is applied. Through the above steps, first conductive layers 5029a to 5032a are formed.
[0100]
By the third etching, impurity regions (LDD regions) 5033 to 5035 that do not overlap with the first conductive layers 5029a to 5032a are formed. Note that the impurity region (GOLD region) 5024 is overlapped with the first conductive layer 5019a.
[0101]
In addition, the electrode formed by the first conductive layer 5019a and the second conductive layer 5019b finally becomes the gate electrode of the n-channel TFT of the driver circuit, and the first conductive layer 5029a and the second conductive layer 5019b The electrode formed with the conductive layer 5029b finally becomes the gate electrode of the p-channel TFT of the driver circuit.
[0102]
Similarly, the electrode formed of the first conductive layers 5030a to 5031a and the second conductive layers 5030b to 5031b finally becomes the gate electrode of the n-channel TFT in the pixel portion, and the first conductive layer 5032a The electrode formed with the second conductive layer 5032b finally becomes the gate electrode of the p-channel TFT in the pixel portion.
[0103]
In this manner, in this embodiment, impurity regions (LDD regions) 5033 to 5035 that do not overlap with the first conductive layers 5029a to 5032a and impurity regions (GOLD regions) 5024 that overlap with the first conductive layer 5019a are formed at the same time. Therefore, it is possible to make them according to TFT characteristics.
[0104]
Next, after removing the resist mask, the gate insulating film 5006 is etched. The etching process here uses CHF as an etching gas. _Three And using a reactive ion etching method (RIE method). In this embodiment, the chamber pressure is 6.7 [Pa], the RF power is 800 [W], the CHF. _Three A third etching process was performed at a gas flow rate of 35 [sccm]. Thus, part of the high concentration impurity regions 5015 to 5018 is exposed, and gate insulating films 5006a to 5006d are formed.
[0105]
Next, a new mask 5036 made of resist is formed, and a third doping process is performed. By this third doping treatment, an impurity element imparting a second conductivity type (p-type) opposite to the first conductivity type (n-type) is added to the semiconductor layer that becomes the active layer of the p-channel TFT. Impurity regions 5037 to 5040 thus formed are formed. (FIG. 3C) The first conductive layers 5029a and 5032a are used as masks for the impurity element, and an impurity element imparting p-type is added to form an impurity region in a self-aligning manner.
[0106]
In this embodiment, the impurity regions 5037 to 5040 are diborane (B ₂ H ₆ ) Using an ion doping method. In the third doping process, the semiconductor layer forming the n-channel TFT is covered with a mask 5036 made of resist. By the first doping process and the second doping process, phosphorus is added to the impurity regions 5037 to 5040 at different concentrations, and the concentration of the impurity element imparting p-type in each of the regions is 2 ×. 10 ²⁰ ~ 2x10 ^{twenty one} [atoms / cm ^Three In order to function as a source region and a drain region of the p-channel TFT, no problem occurs.
[0107]
Through the above steps, impurity regions are formed in the respective semiconductor layers. In this embodiment, the method of doping the impurity (B) after etching the gate insulating film is shown; however, the impurity doping may be performed without etching the gate insulating film.
[0108]
Next, the resist mask 5036 is removed, and a first interlayer insulating film 5041 is formed as shown in FIG. The first interlayer insulating film 5041 is formed of an insulating film containing silicon with a thickness of 100 to 200 [nm] by using a plasma CVD method or a sputtering method. In this embodiment, a silicon oxynitride film having a thickness of 150 [nm] is formed by plasma CVD. Needless to say, the first interlayer insulating film 5041 is not limited to the silicon oxynitride film, and another insulating film containing silicon may be used as a single layer or a stacked structure.
[0109]
Next, a step of activating the impurity element added to each semiconductor layer is performed. This activation process is performed by a thermal annealing method using a furnace annealing furnace. The thermal annealing method may be performed at 400 to 700 [° C.], typically 500 to 550 [° C.] in a nitrogen atmosphere having an oxygen concentration of 1 [ppm] or less, preferably 0.1 [ppm] or less. In this example, the activation treatment was performed by heat treatment at 550 [° C.] for 4 hours. In addition to the thermal annealing method, a laser annealing method or a rapid thermal annealing method (RTA method) can be applied.
[0110]
In this embodiment, simultaneously with the activation treatment, Ni used as a catalyst during crystallization is gettered into impurity regions (5015, 5017, 5037-5038) containing high concentration of P, and mainly channel The nickel concentration in the semiconductor layer that becomes the formation region is reduced. A TFT having a channel formation region manufactured in this manner has a low off-current value and good crystallinity, so that high field-effect mobility can be obtained and good characteristics can be achieved.
[0111]
Further, the activation treatment may be performed before the first interlayer insulating film 5041 is formed. However, when the wiring material used is vulnerable to heat, after forming an interlayer insulating film 5041 (an insulating film containing silicon as a main component, for example, a silicon nitride film) to protect the wiring and the like as in this embodiment. It is preferable to perform an activation treatment.
[0112]
Alternatively, the first interlayer insulating film 5041 may be formed by performing a doping process after the activation process.
[0113]
Further, a process of hydrogenating the semiconductor layer is performed by performing heat treatment at 300 to 550 [° C.] for 1 to 12 hours in an atmosphere containing 3 to 100 [%] hydrogen. In this embodiment, heat treatment was performed for 1 hour at 410 [° C.] in a nitrogen atmosphere containing about 3% of hydrogen. This step is a step of terminating dangling bonds in the semiconductor layer with hydrogen contained in the interlayer insulating film 5041. As another means of hydrogenation, plasma hydrogenation (using hydrogen excited by plasma) may be performed.
[0114]
In the case where a laser annealing method is used as the activation treatment, it is desirable to irradiate a laser beam such as an excimer laser or a YAG laser after performing the hydrogenation.
[0115]
Next, as shown in FIG. 7B, a second interlayer insulating film 5042 made of an organic insulating material is formed over the first interlayer insulating film 5041. In this embodiment, an acrylic resin film having a thickness of 1.6 [μm] is formed. Next, patterning is performed to form contact holes reaching the impurity regions 5015, 5017, and 5037 to 5038.
[0116]
As the second interlayer insulating film 5042, a film made of an insulating material containing silicon or an organic resin is used. As the insulating material containing silicon, silicon oxide, silicon nitride, or silicon oxynitride can be used. As the organic resin, polyimide, polyamide, acrylic, BCB (benzocyclobutene), or the like can be used.
[0117]
In this embodiment, a silicon oxynitride film formed by plasma CVD is formed. Note that the thickness of the silicon oxynitride film is preferably 1 to 5 [μm] (more preferably 2 to 4 [μm]). A silicon oxynitride film is effective in suppressing deterioration of an EL element because it contains a small amount of moisture.
In addition, although dry etching or wet etching can be used for forming the contact hole, it is desirable to use the wet etching method in view of the problem of electrostatic breakdown during etching.
[0118]
Further, since the first interlayer insulating film 5041 and the second interlayer insulating film 5042 are simultaneously etched in the formation of the contact hole here, the material for forming the second interlayer insulating film 5042 is the first material considering the shape of the contact hole. It is preferable to use a material having an etching rate higher than that of the material forming the one interlayer insulating film 5041.
[0119]
Then, wirings 5043 to 5049 that are electrically connected to the impurity regions 5015, 5017, and 5037 to 5038 are formed. Here, a laminated film of a Ti film with a film thickness of 50 [nm] and an alloy film (alloy film of Al and Ti) with a film thickness of 500 [nm] is formed by patterning, but another conductive film is used. May be.
[0120]
Next, a transparent conductive film is formed thereon with a thickness of 80 to 120 [nm] and patterned to form a pixel electrode 5050 (FIG. 7B). In this embodiment, for the pixel electrode 5050, an indium tin oxide (ITO) film or a transparent conductive film in which 2 to 20% zinc oxide (ZnO) is mixed with indium oxide is used.
[0121]
Further, the pixel electrode 5050 is formed in contact with the drain wiring 5048 so as to be electrically connected to the drain region of the EL driving TFT.
[0122]
Next, as shown in FIG. 8A, an insulating film containing silicon (a silicon oxide film in this embodiment) is formed to a thickness of 500 [nm], and an opening is formed at a position corresponding to the transparent electrode 5050. Then, a third interlayer insulating film 5051 functioning as a bank is formed. When the opening is formed, a tapered sidewall can be easily formed by using a wet etching method. Care must be taken because the deterioration of the EL layer due to the step becomes a significant problem unless the side wall of the opening is sufficiently gentle.
[0123]
In this embodiment, a silicon oxide film is used as the third interlayer insulating film 5051. However, an organic resin film such as polyimide, polyamide, acrylic, or BCB (benzocyclobutene) can also be used in some cases. .
[0124]
Next, as shown in FIG. 8A, an EL layer 5052 is formed by an evaporation method, and a cathode electrode (MgAg electrode) 5053 and a protective electrode 5054 are further formed by an evaporation method. At this time, it is preferable that the pixel electrode 5050 be subjected to heat treatment to completely remove moisture before forming the EL layer 5052 and the cathode electrode 5053. In this embodiment, the MgAg electrode is used as the cathode electrode of the EL element, but other known materials may be used.
[0125]
Note that a known material can be used for the EL layer 5052. In this embodiment, a two-layer structure including a hole transporting layer and a light emitting layer is used as an EL layer, but any of a hole injection layer, an electron injection layer, or an electron transport layer is provided. There is also. As described above, various examples of combinations have already been reported, and any of the configurations may be used.
[0126]
In this embodiment, polyphenylene vinylene is formed by a vapor deposition method as a hole transport layer. The light-emitting layer is formed by vapor deposition of 30-40 [%] molecular dispersion of PBD, which is a 1,3,4-oxadiazole derivative, in polyvinyl carbazole. 1% is added.
[0127]
The protective electrode 5054 can protect the EL layer 5052 from moisture and oxygen; however, a passivation film 5055 is preferably provided. In this embodiment, a 300 nm thick silicon nitride film is provided as the passivation film 5055. This passivation film may also be formed continuously without being released to the atmosphere after the protective electrode 5054 is formed.
[0128]
The protective electrode 5054 is provided in order to prevent the cathode electrode 5053 from being deteriorated, and a metal film mainly composed of aluminum is typically used. Of course, other materials may be used. Further, since the EL layer 5052 and the cathode electrode 5053 are very sensitive to moisture, it is desirable that the protective electrode 5054 be continuously formed without being released to the atmosphere to protect the EL layer 5052 from the outside air.
[0129]
Note that the thickness of the EL layer 5052 is 10 to 400 [nm] (typically 60 to 150 [nm]), and the thickness of the cathode electrode 5053 is 80 to 200 [nm] (typically 100 to 150 [nm]. nm]).
[0130]
Thus, an EL module having a structure as shown in FIG. 8A is completed. In addition, in the manufacturing process of the EL module in this embodiment, the source signal line is formed by Ta and W, which are materials forming the gate electrode, and the source and drain electrodes are formed due to the circuit configuration and the process. Although the gate signal line is formed of Al which is the wiring material being used, a different material may be used.
[0131]
Further, according to this embodiment, a driver circuit having an n-channel TFT 5101 and a p-channel TFT 5102 and a pixel portion having a switching TFT 5103 and an EL driving TFT 5104 can be formed over the same substrate.
[0132]
In this embodiment, since the EL element configuration is bottom emission (light emission direction is on the TFT substrate side), the switching TFT 5103 is an n-channel TFT and the EL driving TFT 5104 is a p-channel TFT. Although the configuration of using is shown, the present embodiment is only one preferable mode and need not be limited to this.
[0133]
In this embodiment, the structure in which the EL layer 5052 is formed on the pixel electrode (anode) 5050 and then the cathode electrode 5053 is formed is shown. However, the EL layer and the anode are formed on the pixel electrode (cathode). It is good also as a structure to make. However, in this case, unlike the bottom emission described so far, the top emission is used. At this time, the switching TFT and the EL driving TFT are preferably formed of n-channel TFTs having the low-concentration impurity regions (LDD regions) described in this embodiment.
[0134]
[Example 6]
In the present invention, by using an EL material that can use phosphorescence from triplet excitons for light emission, the external light emission quantum efficiency can be dramatically improved. This makes it possible to reduce the power consumption, extend the life, and reduce the weight of the EL element.
[0135]
Here, a report of using triplet excitons to improve the external emission quantum efficiency is shown.
(T. Tsutsui, C. Adachi, S. Saito, Photochemical Processes in Organized Molecular Systems, ed. K. Honda, (Elsevier Sci. Pub., Tokyo, 1991) p.437.)
The molecular formula of the EL material (coumarin dye) reported by the above paper is shown below.
[0136]
[Chemical 1]

[0137]
(MABaldo, DFO'Brien, Y.You, A.Shoustikov, S.Sibley, METhompson, SRForrest, Nature 395 (1998) p.151.)
The molecular formula of the EL material (Pt complex) reported by the above paper is shown below.
[0138]
[Chemical 2]

[0139]
(MABaldo, S. Lamansky, PEBurrrows, METhompson, SRForrest, Appl. Phys. Lett., 75 (1999) p. 4.)
(T.Tsutsui, M.-J.Yang, M.Yahiro, K.Nakamura, T.Watanabe, T.tsuji, Y.Fukuda, T.Wakimoto, S.Mayaguchi, Jpn.Appl.Phys., 38 (12B (1999) L1502.)
The molecular formula of the EL material (Ir complex) reported by the above paper is shown below.
[0140]
[Chemical 3]

[0141]
As described above, if phosphorescence emission from triplet excitons can be used, in principle, it is possible to realize an external emission quantum efficiency that is 3 to 4 times higher than that in the case of using fluorescence emission from singlet excitons. In addition, the structure of a present Example can be implemented freely combining with any structure of Example 1- Example 9. FIG.
[0142]
[Example 7]
An EL display to which the self-luminous device of the present invention is applied is self-luminous, so that it has excellent visibility in a bright place as compared with a liquid crystal display and has a wide viewing angle. Therefore, it can be used as a display portion of various electronic devices.
[0143]
The EL display includes all information display devices such as a personal computer display device, a TV broadcast reception display device, and an advertisement display device. In addition, the self-luminous device of the present invention can be used for display portions of various electronic devices.
[0144]
Such an electronic device of the present invention includes a video camera, a digital camera, a goggle type display device (head mounted display), a navigation system, a sound reproduction device (car audio, audio component, etc.), a notebook type personal computer, a game device, A portable information terminal (mobile computer, mobile phone, portable game machine, electronic book, or the like), an image playback device equipped with a recording medium (specifically, a recording medium such as a digital video disc (DVD) is played back, and the image is A device provided with a display capable of displaying). In particular, a portable information terminal that is often viewed from an oblique direction emphasizes the wide viewing angle, and thus it is desirable to use an EL display. Specific examples of these electronic devices are shown in FIGS.
[0145]
FIG. 11A illustrates an EL display which includes a housing 3301, a support base 3302, a display portion 3303, and the like. The self-luminous device of the present invention can be used in the display portion 3303. Since the EL display is a self-luminous type, a backlight is not required and a display portion thinner than a liquid crystal display can be obtained.
[0146]
FIG. 11B illustrates a video camera, which includes a main body 3311, a display portion 3312, an audio input portion 3313, operation switches 3314, a battery 3315, an image receiving portion 3316, and the like. The self-luminous device of the present invention can be used in the display portion 3312.
[0147]
FIG. 11C shows a part (right side) of a head mounted EL display, which includes a main body 3321, a signal cable 3322, a head fixing band 3323, a display portion 3324, an optical system 3325, a display device 3326, and the like. The self-luminous device of the present invention can be used in the display device 3326.
[0148]
FIG. 11D shows an image reproducing device (specifically, a DVD reproducing device) provided with a recording medium, which includes a main body 3331, a recording medium (DVD or the like) 3332, an operation switch 3333, a display unit (a) 3334, a display unit. (b) 3335 and the like are included. The display unit (a) 3334 mainly displays image information, and the display unit (b) 3335 mainly displays character information. However, the self-luminous device of the present invention includes the display unit (a) 3334 and the display unit (b) 3335. Can be used. Note that an image reproducing device provided with a recording medium includes a home game machine and the like.
[0149]
FIG. 11E illustrates a goggle type display device (head mounted display), which includes a main body 3341, a display portion 3342, and an arm portion 3343. The self-luminous device of the present invention can be used in the display portion 3342.
[0150]
FIG. 11F illustrates a personal computer, which includes a main body 3351, a housing 3352, a display portion 3353, a keyboard 3354, and the like. The self-luminous device of the present invention can be used in the display portion 3353.
[0151]
If the emission brightness of the EL material is increased in the future, the light including the output image information can be enlarged and projected by a lens or the like and used for a front type or rear type projector.
[0152]
In addition, the electronic devices often display information distributed through electronic communication lines such as the Internet and CATV (cable television), and in particular, opportunities to display moving image information are increasing. Since the response speed of the EL material is very high, the EL display is preferable for displaying moving images.
[0153]
In addition, since the EL display portion consumes power, it is desirable to display information so that the light emission portion is reduced as much as possible in order to save power consumption. Therefore, when an EL display is used for a display unit mainly including character information, such as a portable information terminal, particularly a mobile phone or an audio reproduction device, it is driven so that character information is formed by the light emitting part with the non-light emitting part as the background. It is desirable to do.
[0154]
FIG. 12A illustrates a mobile phone, which includes a main body 3401, an audio output portion 3402, an audio input portion 3403, a display portion 3404, operation switches 3405, and an antenna 3406. The self-luminous device of the present invention can be used in the display portion 3404. Note that the display portion 3404 can reduce power consumption of the mobile phone by displaying white characters on a black background.
[0155]
FIG. 12B shows a sound reproducing device, specifically a car audio, which includes a main body 3411, a display portion 3412, and operation switches 3413 and 3414. The self-luminous device of the present invention can be used in the display portion 3412. Moreover, although the vehicle-mounted audio is shown in the present embodiment, it may be used for a portable or household sound reproducing device. Note that the display portion 3414 can reduce power consumption by displaying white characters on a black background. This is particularly effective in a portable sound reproducing apparatus.
[0156]
FIG. 12C illustrates a digital camera, which includes a main body 3501, a display portion (A) 3502, an eyepiece portion 3503, operation switches 3504, a display portion (B) 3505, and a battery 3506. The electro-optical device of the present invention can be used in the display portion (A) 3502 and the display portion (B) 3505.
[0157]
As described above, the applicable range of the present invention is so wide that it can be used for electronic devices in various fields. Moreover, any configuration shown in the first to fifth embodiments may be applied to the electronic apparatus of the present embodiment.
【The invention's effect】
According to the self-light-emitting device of the present invention, it is possible to provide a self-light-emitting device capable of correcting the deterioration of the EL element due to the difference in lighting time on the circuit side and displaying a uniform screen without uneven brightness.
[Brief description of the drawings]
FIG. 1 is a block diagram of a self-luminous device having a deterioration correction function of the present invention.
FIG. 2 is a diagram illustrating a correction method using addition processing.
FIG. 3 is a diagram showing a correction method by subtraction processing.
FIG. 4 is a block diagram showing an example of a self-luminous device when a display device and a signal correction device are integrally formed on the same substrate.
FIG. 5 is a diagram illustrating an example of a manufacturing process of an active matrix self-luminous device.
FIG. 6 is a diagram illustrating an example of a manufacturing process of an active matrix self-luminous device.
FIG. 7 is a diagram illustrating an example of a manufacturing process of an active matrix self-luminous device.
FIG. 8 is a diagram illustrating an example of a manufacturing process of an active matrix self-luminous device.
FIG. 9 is a diagram illustrating a time gray scale method.
FIG. 10 is a diagram showing occurrence of luminance unevenness on a screen due to deterioration of a light emitting element.
FIG. 11 is a diagram showing an application example of the self-luminous device having the deterioration correction function of the present invention to an electronic device.
FIG. 12 is a diagram showing an application example of the self-luminous device having the deterioration correction function of the present invention to an electronic device.
FIG. 13 is a block diagram of a self-luminous device having a deterioration correction function of the present invention.
FIG. 14 is a block diagram of a source signal line driving circuit of a digital video signal input method and an analog signal input method in a self-light-emitting device having a deterioration correction function of the present invention.
FIG. 15 is a diagram showing an example of a conventional self-luminous device.

Claims (7)

A pixel portion having a plurality of pixels including self-luminous elements;
A counter unit for detecting a lighting time by counting the number of times the self-light emitting element is turned on for each pixel by sampling the first digital video signal;
A storage circuit unit for accumulating the lighting time of the light emitting element detected by the counter unit, and storing the accumulated lighting time of the self light emitting element;
By referring to the accumulated lighting time of the self-light-emitting element stored in the storage circuit unit and the time-dependent data of the luminance characteristics of the self-light-emitting element stored in the correction data storage unit, the first digital A signal correction unit that corrects the video signal and outputs a second digital video signal;
The pixel unit displays a video in a time gray scale method according to the second digital video signal,
The memory circuit unit includes a volatile memory in which data of lighting time of the self-luminous element is written from the counter unit when the pixel unit is operating, and the self-luminous element from the volatile memory at regular intervals. A self-light-emitting device having a nonvolatile memory in which data of cumulative lighting time of a light-emitting element is written. In claim 1,
The pixel includes a first transistor and a second transistor,
In the first transistor, a gate is electrically connected to a gate signal line, one of a source and a drain is electrically connected to a source signal line, and the other of the source and the drain is electrically connected to a gate of the second transistor,
In the second transistor, one of a source and a drain is electrically connected to the self-light emitting element, and the other of the source and the drain is electrically connected to a current supply line. In claim 1 or claim 2,
The pixel unit, the counter unit, the storage circuit unit, and the signal correction unit are formed on the same substrate. In any one of Claims 1 thru | or 3,
a driving circuit that performs signal processing of n + m bits (n and m are natural numbers, n ≧ 2);
The second digital video signal written to the pixel including the self-light-emitting element that is determined not to have deteriorated due to the cumulative lighting time of the self-light-emitting element is a digital video signal for n bits,
The cumulative lighting time of the self-luminous element, the second digital video signal degradation is written to the pixel including the self-luminous elements is determined to be occurring is, n + m bit portion of the digital video signal A self-luminous device characterized by the above. In any one of Claims 1 thru | or 3,
The second digital video signal is added to the second digital video signal written to the pixel including the self-light-emitting element determined to be deteriorated by the cumulative lighting time of the self-light-emitting element. A self-light-emitting device, wherein a correction amount of a video signal is set to be larger than a correction amount of the second digital video signal written to the pixel including the self-light-emitting element that is determined not to have deteriorated. In claim 2,
By performing a subtraction process on the second digital video signal written to the pixel including the self-light-emitting element that is determined not to have deteriorated due to the cumulative lighting time of the self-light-emitting element, the second digital video signal is obtained. A correction amount of the video signal is smaller than a correction amount of the second digital video signal written to the pixel including the self-luminous element determined to have deteriorated ,
In the pixel including the self-light-emitting element that has been determined not to have deteriorated, the potential of the current supply line is changed to compare the voltage between both electrodes of the self-light-emitting element before the subtraction process is performed. Then, the self-light-emitting device is characterized in that the voltage between both electrodes of the self-light-emitting element after the subtraction process is performed is increased.   The electronic device using the said self-light-emitting device of any one of Claim 1 thru | or 6.

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